Heater Stuck On

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CamMoore
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Re: Heater Stuck On

Post by CamMoore »

- Sensor duff (pretty common) - it's the one facing towards the front on the stat housing. Try pulling the connector off and shorting the 2 connector sockets on the plug on the wire with a paper clip or similar. This should send the gauge quickly over to max. If it does, then it is a faulty sensor (if ordering a new one, be careful to order the right one !!)

Just one more thing. How do you remove the sensor without coolant pouring out?

CamMoore
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Re: Heater Stuck On

Post by CamMoore »

Don't worry I figured it out. It looks like it was the sensor.

I have been driving around for the last three years without that temp sensor working, does that mean that my thermostat hasn't been letting coolant into my engine?

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ghost123uk
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Re: Heater Stuck On

Post by ghost123uk »

CamMoore wrote:I have been driving around for the last three years without that temp sensor working, does that mean that my thermostat hasn't been letting coolant into my engine?
Now here we must take that as you having a joke with us.................................................yes ?





Just in case you’re not joking ;) = If no coolant was let into you're engine, it would overheat and seize up solid in about 15 minutes of driving, and then you would almost for sure need a to buy another engine (about £1500 in the UK)
Got a new van, but it's a 165bhp T4 [shock horror] Accurate LPG Station map here

CamMoore
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Re: Heater Stuck On

Post by CamMoore »

Hahah I was writing that while on the go :rollin . Let me rephrase that, does that mean the flow of coolant into the engine will be affected? Or is that another sensor?
Is the temp sensor just for the gauge?

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ghost123uk
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Re: Heater Stuck On

Post by ghost123uk »

Yes, that forward facing sensor is just for the gauge. (the other one, side facing, is for the carburettor heating element for cold starting assistance, or similar function if using the fuel injection versions, which I know less about).

The only thing that controls the flow of coolant around your engine is the thermostat.

If it has been removed for some reason, or it is stuck open (not unheard of) too much coolant will flow around your engine and front radiator, making the engine run too cool. You can test thermostats in a pan of boiling water. If ever attempting to remove your thermostat, take care when attending to the four bolts on the plastic housing. They often seize up, can be a bugger to get out, and can damage the plastic housing. Replacement housings are available again now, but best to not have to source one unless you have to ;) Use PlusGas on stuck nuts and bolts (NOT WD40 !!) and using well fitting good quality tools goes a long way to preventing issues.
Got a new van, but it's a 165bhp T4 [shock horror] Accurate LPG Station map here

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Smiffo
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Re: Heater Stuck On

Post by Smiffo »

ghost123uk wrote:
CamMoore wrote:I have been driving around for the last three years without that temp sensor working, does that mean that my thermostat hasn't been letting coolant into my engine?
Now here we must take that as you having a joke with us.................................................yes ?





Just in case you’re not joking ;) = If no coolant was let into you're engine, it would overheat and seize up solid in about 15 minutes of driving, and then you would almost for sure need a to buy another engine (about £1500 in the UK)

Or......... Rather than buy an engine, he could buy an airline ticket for you to fly out and repair it..!!?? :idea
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CamMoore
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Re: Heater Stuck On

Post by CamMoore »

So I removed the plug and bridged the connectors together and the gauge went right to max. I have since replaced the sensor and gauge moves but only slightly. It's a pretty warm day here (about 28 degrees celsius), I let the van idle for about 15 minutes then took it for a 10 minute drive and the needle sits in the white area (see photo). Is this normal?

Where is it normally meant to sit?

Image

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ghost123uk
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Re: Heater Stuck On

Post by ghost123uk »

It should sit somewhere near the middle.

Assuming that the sensor is:-
A) - The correct one
and
B) - Of a decent manufacturer

Then the chances are you’re thermostat is either stuck open or maybe not even there (did this temp gauge issue recently occur?)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Slight aside = I changed my temp gauge sensor earlier this year as my gauge was reading like yours. I had previously fitted a new stat (from Brickwerks) so I knew it wasn't that. The new sensor worked fine and set my needle in the middle. However a few months later and it has started to read low again, not as low as yours, but it only goes about 1/3rd the way up. I checked my vans coolant temp by pointing one of those hand held infra red temperature readout guns at a fat hose in the engine bay when the engine was well up to temperature and it read about 86 degrees, showing that the engine was up to it's correct temperature and it looks like my new sensor has prematurely gone faulty :evil: It was purchased from a very reputable supplier ;). I will have to get another at some point, but it can wait now until warmer weather.
Got a new van, but it's a 165bhp T4 [shock horror] Accurate LPG Station map here

MidLifeCrisis
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Re: Heater Stuck On

Post by MidLifeCrisis »

CamMoore wrote:So I removed the plug and bridged the connectors together and the gauge went right to max. I have since replaced the sensor and gauge moves but only slightly. It's a pretty warm day here (about 28 degrees celsius), I let the van idle for about 15 minutes then took it for a 10 minute drive and the needle sits in the white area (see photo). Is this normal?

Where is it normally meant to sit?

Image
Do you have access to any electrical resistors? If so, you can put a 35-40ohm resistor across the two sensor connector points and the gauge should move to the hot position (position 'II' in the pic below); you could also try a 250-270ohm resistor which should move the needle to the cold position (position 'I' in the pic below);
This would at least prove that the circuit is working correctly? Although to be fair, your test of shorting the connector pins together proves that it pretty much works??

Image

Any chance your coolant is low??
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CamMoore
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Re: Heater Stuck On

Post by CamMoore »

I've started a new thread here:
https://club8090.co.uk/forum/viewtopic.php?f=39&t=148091" onclick="window.open(this.href);return false;

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